In recent years, development of radio communication technologies have advanced to the extent that products wherein a radio communication function is added to a communication apparatus such as a facsimile apparatus are appearing. On the other hand, there is increasing necessity to send and receive image data because of the spread of digital cameras and color printers.
In such situation, a method of efficiently performing image communication is disclosed in Japanese Patent Laid-Open No. 10-224591. The Japanese Patent Laid-Open No. 10-224591 describes that a single digital radio line is time-division-multiplexed into a low-speed radio data communication channel of 32 Kbps or so and a high-speed radio data communication channel of 400 Kbps or so, and the low-speed radio data communication channel is used when accessing a public switched line and the high-speed radio data communication channel is used when not accessing a public switched line.
Meanwhile, there are facsimile apparatuses of recent years having an image reading section (hand scanner) capable of being removed from the apparatus main body for use. In the case where the communication method disclosed in the Japanese Patent Laid-Open No. 10-224591 is applied to such a facsimile apparatus, since this method uses the single radio line, it is necessary to mount a radio processing section on the facsimile main body in order to allow a cordless telephone accommodated in the extension to access the public switched line via the facsimile apparatus by radio communication in a state where the hand scanner has come off.
Accordingly, in the above conventional communication method, there is a problem that the image reading section (hand scanner) must be set in order to send an image read by the facsimile to another terminal.
In addition, in the case of performing the high-speed radio data transmission of 400 Kbps or so by the above-mentioned conventional method, the communication is performed in the frequency hopping mode in a 2.4 GHz band. In this mode, however, there is a problem that radio interference is apt to occur since each individual channel does not occupy a specific frequency, which is different from the case of the time division multiple access (TDMA). Therefore, it is not suitable for audio communication and the like, and thus there is a problem that it is difficult to implement a cordless telephone function often used in the facsimile apparatuses of recent years.